HOST: Life in the Sonoran is full of surprises.

It rains in the summer, sometimes

violently, making it just wet enough to sustain

a semi-arid version of the Midwestern grasslands.

And with grasslands come the US's most iconic

grass cutter, the prairie dog.

[music playing]

Prairie dogs are, of course, not dogs at all,

but are in fact closely related to ground squirrels.

Old-timers named them for their dog-like bark.

[yip]

That's no simple yip.

Scientists currently believe that prairie dogs--

[yipping]

--have the most sophisticated vocal animal

language ever decoded.

[music playing]

They needed to warn each other.

[yipping]

Because in the Sonoran, of a lot of things like to eat them,

including the badger.

[music playing]

They dig a complex system of burrows.

But most mornings, they have to leave to harvest grass.

It's a risky time.

So while one feeds, another will keep a look out.

It takes a very social animal to be this co-operative.

They groom each other a bit like monkeys do.

And young prairie dogs love to play fight.

[music playing]

The center of prairie dog life is

the family, ruled by a dominant male with a few females.

Families can live in large neighborhoods of thousands.

Even as organized as they are, it's still

tough to be a prairie dog.

Only half live past their first year.